Projectile for smooth bore weapons



p 19384- E. w. BRANDT 2,113,313

PROJECTILE FOR SMOOTH BORE WEAPONS Filed March 11, 1957 Patented Apr. 1938 PROJECTILE FOR SMOOTH BORE WEAPONS Edgar William Brandt, Paris, France, assignor to Sageb, Socit Anonyme de Gestion et d'Ex- Dioitation de Brevets, ,Fribourg, Switzerland, a corporation of Switzerland Application March 11, 1937, Serial No. 130,402

In France March 13, 1936 1 Claim. (01. 102-29) This invention relates to a projectile intendedtobe fired i rom smooth bore weapons, such as mortars. trench mortars and the like. It is more particularly suitable for weapons of this kind.

a flringwith initial velocitiesof 100 to 400 metres 'per second.

,, The projectile of the present invention is of the type comprising an ogival'irontal port on,

- connected bya cylindrical portion witha tape ng l0 rearward portion to which is attached a cylindrical tall, the extremity of which carries' stabilizing vanes.

.The projectile of the present invention is primarily characterized in that the several component portions thereof have the following approximate longitudinal dimensions, expressed in calibres: I

Ogival portion 2 Y Cylindrical portion. 0.65 =Tapering rearward portion 2.2

Cylindrical tail 1.7 arid lanes 0.65

making a total length of 'about "1.2 calibres The length 01' one or more 0! the partsof the projectile may vary by il0%.

According to another characteristic of the invention, the whole is so arranged that the centre of gravity of. the loaded projectile is located at a point about 9.40 calibre behind therear extremity. ot the cylindrical portion, whilst the centre of resistance is at a point about 1 calibre behindthe rear extremity of said cylindrical portion. e

The foregoing arrangement ensures the maxi mum range oi the projectile with a given propellant charge, and at the same time, a high degree of accuracy. I

Further features and advantages of the invention will become apparent from the following lurther description thereof.

In order' more clearly to understand the invention, reference is made to the accompanying drawing, which illustrates'diagrammatically and by way of example, one embodiment thereof and in which:

Fig. 1 is an elevation; and Fig.2isanendview.

The embodiment illustrated is intended to repto resent a 120 mm. projectile, the projectile com-.

prising a frontal portion i. in the form of a ,slender ogive with an angle of ogrve between 35 The ogive l connectsrpreferably tangentially,-

" with a cylindrical portiohi, provided with sealing grooves 4, of known type, forming a pneumatic joint between the projectile and the walls of the bore of the gun. The length of this band is about 0.65 calibre.

Beyond the band 3, the body of the projectile comprises a portion .5 which tapers towards the rear (in the form of a cone, ogive or otherwise) and has a length of about 2.2 'calibres. 10

The walls of the projectile become stouter as they advance from the band-3, so that,'near the forward extremity, at 6, they are about twice as thick as the walls of the band, at 1. Over the whole length of the rearward portion 5, the i5 thickness of the walls remains approximately the same as in line with the band, and does not increase until'the base, at 8. The body of the projectile terminates in a cylindrical heel 9, to which is attached an also 20 cylindrical tail ill serving to support radial vanes ii. The length of the cylindrical portion comprised between the rear edge on the part 5' and the root of the vanes is about 1.7 calibres. The diameter of this portion of the projctile'is prei- 25 erably a little smaller than that of the rear edge; i211. The length selected for the vanes ii is about 0.65 calibre. As shown in the drawing, the leading edges i2of the vanes are preferably given a backward sweep in relation to the direc- 30 tion of flight of the projectile. Projections Ii on .the rear ends of the vanes serve to 'guide the projectile in the gun.

The tail I0 is of tubular form, and houses the propellant charge (cartridge), vthe gases 0P described in the U. S. Patent No. 2,052,546 dated September 1, 1936. A small collar l5a,-or equivalent checking device, may be provided on the tail iii, to prevent the charges l5 from slipping beyond the region of the openings H. The propor- 45 tions specified for the several portions of the projectile are given merely by way of approximation as previously stated, one or'more of them may vary by i10%.

The projectile is arranged in such a manner that the centre of gravity G of the loaded projectile is preferably located at a point about 0.40 calibre behind the rear end of the cylindrical zone; the centre of resistance R (point of application of the resultant of the aerodynamic pressures on the projectile) being located at a distance comprised between 0.90 and 1.5 calibres behind the rear end of the said cylindrical zone.

It is obvious that the invention is capable of various modifications and alterations without departing from the spirit and scope thereof as delined in the appended claim.

I claim:

A projectile for smooth-bore weapons comprising a body including consecutively from thefront to the rear thereof, an ogival front part, a full calibre cylindrical guiding part engaging the bore of the weapon and into which said ogival front part merges, and a rearward tapering part; a tail fixed to the rear end of said body, vanes mounted at the rear end of said tail and having the same diameter as that of said cylindrical guiding part, and a time at the front end of said body adapted to cause bursting of the projectile; the iength of said ogival front part with said fuse being between 1.8 and 2.0 calibres, the length of said cylindrical guiding part being between 0.65 and 0.72

calibres, the length of said rearward tapes 5 part being between 2.20 and 2.42 calibres. the length of said tail up to the front side of said vanes being between 1.60 and 1.75 calibres and the length of said vanes being between 0.65 and 0.75 calibres; the center of gravity of the projec'tile being located at a distance of between 0.35 and 0.45 calibres in rear of the rear end of said cylindrical guiding part and the center of r- .sistance being located at a distance of between 1.30 and 1.50 calibres in rear of the rear end of said cylindrical guide part.

EDGAR WILLIAM BRANDT.- 

